132 
ORGANOGRAPHY. 
BOOK I. 
the place of wliich is occupied by bracts, supported by other 
bracteai which enclose no flowers, and when with such a form- 
ation the rachis, which is flexuose and toothed, does not fall 
off with the flowers, as in Grasses, each part of the inflo- 
rescence so arranged is called a spikelet or locusta (epillet, Dec. ; 
paquet, Tournefort). 
When the flowers are closely arranged around a fleshy 
rachis, which is enclosed in the kind of bract called a spathe 
(see p. 125.), the inflorescence is termed a spadix (spadice or 
poinfoUi Fr.), (j^^. 85.). This is only known to exist in Aroi- 
deas and Palms. It is frequently terminated, as at Ji(/. 85., by a 
soft club-shaped mass of cellular substance which extends far 
beyond the flowers, and is itself entirely naked : this is an in- 
stance of a growing point altogether analogous to what forms 
the spine of a branch, except that it is soft and blunt, instead 
of being hard and sharp-pointed. 
The raceme has been said to differ from the spike only in 
its flowers being pedicellate : to this must be added, that the 
pedicels are all of nearly equal length ; but in many plants, as 
Alyssum saxatile, the lower pedicels are so long that their 
flowers are elevated to the same level as that of the upper- 
most flowers ; a corymb is then formed {fig* 87.). This term 
is frequently used in an adjective sense, to express a similar 
arrangement of the branches of a plant or of any other kind 
of inflorescence : thus, in Stevia, the branches are said to be 
corymbose ; in others, the panicle is said to be corymbose ; 
and so on. When corymbose branches are very loose and 
irregular, they have given rise to the term muscarium; a name 
formerly used by Tournefort, but not now employed. 
If the expansion of an apparent corymb is centrifugal, in- 
stead of centripetal ; that is to say, commences at the centre, 
and not at the circumference, as in Dianthus Carthusianorum, 
we then hdiYe the fascicle (fig. &S.) ; a term which may not 
incorrectly be understood as synonymous with compound co- 
rymb. The modern corymb must not be confounded with that 
of Pliny, which was analogous to our capitulum. 
When the pedicels all proceed from a single point, as in 
Astrantia, and are of equal length, or corymbose, we have 
what is called an umbel {fig. 80.). If each of the pedicels 
